Data storage devices store digital information on a rotating disc. Heads are supported relative to the disc surface to read data from or write data to the disc. For proximity or near proximity recording, transducer elements are carried on an air bearing slider to form a data head to read data from or write data to the disc. The slider is flexibly coupled to a suspension assembly to pitch and roll relative to the disc surface. The suspension assembly supplies a load force to the slider at a load point about which the slider pitches and rolls.
Suspension assemblies are supported by actuator arms of an actuator block to move the slider or head relative to selected data tracks on the disc surface. For operation, rotation of the disc creates an air flow along the air bearing of the slider to create a hydrodynamic lifting force. The hydrodynamic lifting force is countered by the load force supplied by the suspension assembly so that the slider or head flies above the disc surface at a fly height defined in part by the hydrodynamic lifting force of the air bearing and the load force supplied by the suspension assembly. Variations in fly height parameters can affect read/write operations.
Prior to operation, the slider is parked on the disc surface for contact starts and stops (CSS). The interface between the slider and a lubricant film layer on the disc surface creates a stiction force holding the slider to the disc surface. For operation, sufficient power must be supplied so that the hydrodynamic lifting force overcomes the stiction force holding the slider to the disc surface for CSS. If the stiction force is too high, the slider will stick to the disc surface and “spin-up” operation of the CSS drive will fail. Thus, it is desirable to control the stiction force holding the slider to the disc surface for CSS.
Disc drive are susceptible to non-operational shock or vibration due to transport, installation or other reasons. Shock or impact to the disc drive can introduce vibration or movement of the head relative to the disc surface which can damage the head components and the disc surface. Damage to the head and disc surface can degrade read-write operations of the disc drive and introduce thermal asperities. The present invention addresses these and other problems and offers solutions not previously recognized nor appreciated.